Service key



FIG. 1 is a top, front, right perspective view of a service key in accordance with my design;

FIG. 2 is a top, right, rear perspective view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a front elevational view thereof;

FIG. 5 is a top plan view thereof, with the bottom view being a mirror image thereof; and,

FIG. 6 is a right side elevational view thereof, with the left side elevational view being a mirror image thereof. 

The ornamental design for a service key, as shown and described. 